Today is the 96th commemoration of Mother's Day, when children of all ages offer thanks to the women who shoulder the world's toughest job. Today also is a signal moment in the history of motherhood: the 50th anniversary of the federal government's intent to approve the birth-control pill.

The pill redefined modern society by conferring the power to reliably control the roulette wheel of pregnancy. The pill bought a woman time, to finish an education, to go to work, to hike the Cascades. The pill made motherhood a choice, not a destiny - a concept that many young women today find hard to grasp.

"The biggest thing is that they cannot imagine a world in which they have virtually no control over their reproductive decisions," said Melody Rose, a political scientist who is director of the Center for Women, Politics and Policy at Portland State University. "There's a full generation of Americans who have little or no connection to that time in our history."

Before the pill, a woman in Oregon had her first child at 21, on average. The U.S. Statistical Abstract from 1960 reports that slightly less than half of all mothers held a high school diploma; only about 10 percent had any college education. More than 60 percent of mothers were not in the work force, either.

But once women could get the pill, the game changed.

"For the first time, it allowed women to be in control of their own fertility, which had huge benefits to women who have aspirations other than raising children," said David Greenberg, president and chief executive officer of Planned Parenthood Columbia Willamette.

"And because it allowed them to space their children and control the size of their families, it allowed them to balance families with work life."

Today, a woman in Oregon has her first child at age 25, four years later than 50 years ago. More than 60 percent of mothers have finished high school, and more than half are in the work force.

Preliminary state figures for the first three months of this year show that 64 percent of Oregon mothers were married upon giving birth - the high was Wallowa County's 81.3 percent, the low Grant County's 37.5 percent.

In 2009, Oregon was the place of birth for 46,327 lives, down from a 10-year high of 49,373 in 2007. If numbers from the first quarter of 2010 hold through the year, Oregon could see a steep drop in the number of births to around 40,000.

The advent of the pill was not universally acclaimed. Not until 1965 did the U.S. Supreme Court rule that state bans on contraception violated a married woman's right to privacy. It wasn't until 1972 that the court decided that unmarried women had a privacy right to contraception, too.

In 1968, the Roman Catholic Church prohibited its members from using artificial birth control, a rule that stands to this day. While no other denomination has as explicit a ban, each religious group runs a spectrum: Orthodox Judaism, for example, discourages birth control; the Reform wing, however, leaves the decision to the couple.

A report released last week from the Pew Research Center's Social & Demographic Trends shows that the pill, while a power unto itself, blends with other forces to change how women become mothers.

The Pew report says 20 years ago, teens gave birth to 13 percent of the nation's babies, while women older than 35 bore 9 percent of the babies. In 2008, though, the teen birth rate dropped to 10 percent, while the rate for women older than 35 went up to 14 percent.

"Not only did the pill allow women to imagine themselves differently as individuals," said Rose, "it also gave them permission to become politically active, to seek careers, to engage in their community in a way that they weren't able to do."